Title

High magnetic field water and metabolite proton T<sub>1</sub> and T<sub>2</sub> relaxation in rat brain in vivo.

Authors

de Graaf, Robin A.; Brown, Peter B.; McIntyre, Scott; Nixon, Terence W.; Behar, Kevin L.; Rothman, Douglas L.

Abstract

Comprehensive and quantitative measurements of T1 and T2 relaxation times of water, metabolites, and macromolecules in rat brain under similar experimental conditions at three high magnetic field strengths (4.0 T, 9.4 T, and 11.7 T) are presented. Water relaxation showed a highly significant increase ( T1) and decrease ( T2) with increasing field strength for all nine analyzed brain structures. Similar but less pronounced effects were observed for all metabolites. Macromolecules displayed field-independent T2 relaxation and a strong increase of T1 with field strength. Among other features, these data show that while spectral resolution continues to increase with field strength, the absolute signal-to-noise ratio (SNR) in T1/ T2-based anatomical MRI quickly levels off beyond ∼7 T and may actually decrease at higher magnetic fields. Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc.

Publication

Magnetic Resonance in Medicine, 2006, Vol 56, Issue 2, p386

ISSN

0740-3194

Publication type

Academic Journal

DOI

10.1002/mrm.20946